The psychologist David Marks criticized the book for endorsing pseudoscience. Marks noted that Koestler uncritically accepted ESP experiments and ignored evidence that did not fit his hypothesis. Marks coined the term "Koestler's Fallacy" as the assumption that odd matches of random events cannot arise by chance. Marks illustrates the fact that such odd matches do regularly occur with examples from his own experience.[1]John Beloff gave the book a mixed-review, describing it as "a typical Koestlerian performance" but noted that some of his claims about psychical research were inaccurate.[2]